Trait opencv::hub_prelude::KNearestConst

pub trait KNearestConst: StatModelConst {
    fn as_raw_KNearest(&self) -> *const c_void;

    fn get_default_k(&self) -> Result<i32> { ... }
    fn get_is_classifier(&self) -> Result<bool> { ... }
    fn get_emax(&self) -> Result<i32> { ... }
    fn get_algorithm_type(&self) -> Result<i32> { ... }
    fn find_nearest(
        &self,
        samples: &dyn ToInputArray,
        k: i32,
        results: &mut dyn ToOutputArray,
        neighbor_responses: &mut dyn ToOutputArray,
        dist: &mut dyn ToOutputArray
    ) -> Result<f32> { ... }
}

The class implements K-Nearest Neighbors model

See also

@ref ml_intro_knn

Required Methods

fn as_raw_KNearest(&self) -> *const c_void

Provided Methods

fn get_default_k(&self) -> Result<i32>

Default number of neighbors to use in predict method.

See also

setDefaultK

fn get_is_classifier(&self) -> Result<bool>

Whether classification or regression model should be trained.

See also

setIsClassifier

fn get_emax(&self) -> Result<i32>

Parameter for KDTree implementation.

See also

setEmax

fn get_algorithm_type(&self) -> Result<i32>

%Algorithm type, one of KNearest::Types.

See also

setAlgorithmType

fn find_nearest(
    &self,
    samples: &dyn ToInputArray,
    k: i32,
    results: &mut dyn ToOutputArray,
    neighbor_responses: &mut dyn ToOutputArray,
    dist: &mut dyn ToOutputArray
) -> Result<f32>

Finds the neighbors and predicts responses for input vectors.

Parameters

• samples: Input samples stored by rows. It is a single-precision floating-point matrix of <number_of_samples> * k size.
• k: Number of used nearest neighbors. Should be greater than 1.
• results: Vector with results of prediction (regression or classification) for each input sample. It is a single-precision floating-point vector with <number_of_samples> elements.
• neighborResponses: Optional output values for corresponding neighbors. It is a single- precision floating-point matrix of <number_of_samples> * k size.
• dist: Optional output distances from the input vectors to the corresponding neighbors. It is a single-precision floating-point matrix of <number_of_samples> * k size.

For each input vector (a row of the matrix samples), the method finds the k nearest neighbors. In case of regression, the predicted result is a mean value of the particular vector’s neighbor responses. In case of classification, the class is determined by voting.

For each input vector, the neighbors are sorted by their distances to the vector.

In case of C++ interface you can use output pointers to empty matrices and the function will allocate memory itself.

If only a single input vector is passed, all output matrices are optional and the predicted value is returned by the method.

The function is parallelized with the TBB library.

C++ default parameters

• neighbor_responses: noArray()
• dist: noArray()

Implementors

impl KNearestConst for PtrOfKNearest